A nonvolatile memory device includes at least one switching device and at least one storage node electrically connected to the at least one switching device. The at least one storage node includes a lower electrode, one or more oxygen-deficient metal oxide layers, one or more data storage layers, and an upper electrode. At least one of the one or more metal oxide layers is electrically connected to the lower electrode. At least one of the one or more data storage layers is electrically connected to at least one of the one or more metal oxide layers. The upper electrode is electrically connected to at least one of the one or more data storage layers. A method of manufacturing the nonvolatile memory device includes preparing the at least one switching device and forming the lower electrode, one or more metal oxide layers, one or more data storage layers, and upper electrode.